Genetic Research Provides Insights Into Age-Related Macular Degeneration

Abstract

WITH NO CURE AND A PREVAlence twice that of Alzheimer disease, age-related macular degeneration (AMD) is increasingly being recognized as a serious condition that leads to vision loss in a growing number of elderly persons. While a clear heritable component to the disease has been known for years, only recently have investigators begun to tease out the alterations in genetic pathways—particularly those involving complement and to some extent cholesterol—that play a role. Researchers have also learned that individuals who are genetically predisposed can take steps to ward off the disease. Studies indicate that a combination of environmental and hereditary risk factors confer a greater risk of AMD than that conferred by each risk factor individually. Experts are optimistic that this wealth of new information will spur additional discoveries that could ultimately delay or prevent AMD, making it one of the first major chronic diseases to benefit from pharmacogenetics and personalized medicine. “Twenty years ago, there was nothing we could do about AMD,” said Gregory Hageman, PhD, the John A. Moran Presidential Professor of Ophthalmology and Visual Sciences and director of the Moran Center for Translational Medicine at the University of Utah in Salt Lake City. “Now I’d say it’s the best understood complex trait disease out there, and I believe that in 2 to 3 years out we’ll be delivering some real benefits to patients,” he added. More than 85% of all individuals with intermediate or advanced AMD have the dry form of the disease, which occurs when the light-sensitive cells in the macula slowly break down and gradually blur central vision. Among patients with advanced AMD, about twothirds have the wet form of the disease,